Since the publication of a 3rd Generation Partnership Project Release 7 (3GPP Release7) standard system, a policy and charging function has been implemented by a Policy and Charging Control (PCC) Framework. The PCC Framework is a functional framework that can be used for multiple access technologies, for example: the PCC Framework can be used for Terrestrial Radio Access Networks (UTRANs) on the Universal Mobile Telecommunications System (UMTS), radio access networks and Intercommunication Wireless LANs (I-WLANs) on the Global System for Mobile Communication (GSM)/Enhanced Data Rate for GSM Evolution (EDGE), Evolved Packet Systems (EPSs) and the like.
The PCC mainly implements two major functions of policy control and charging. FIG. 1 is a schematic diagram illustrating a non-roaming architecture of existing PCC of Rel-11. The functionalities of individual logic functions and their interfaces within the PCC architecture shown in FIG. 1 are described as follows.
An Application Function (AF), which is used to provide an access point for service applications, where dynamic policy control is required to be performed on network resources used by these service applications. When conducting parameter negotiation on a service plane, the AF transfers related service information to a Policy and Charging Rules Function (PCRF). If these service information is consistent with the policy of the PCRF, then the PCRF accepts the negotiation. If these service information is consistent with the policy of the PCRF, then the PCRF rejects the negotiation and provides PCRF-acceptable service parameters during feedback. Then, the AF may return these parameters to a User Equipment (UE). Here, the interface between the AF and the PCRF is a Rx interface.
The PCRF is the core of the PCC, and is used to formulate policy decisions and charging rules. The PCRF provides a network control rule based on service data traffic. Such network control includes detection of the service data traffic, gating control, Quality of Service (QoS) control, and a data-traffic-based charging rule. The PCRF sends the policy and charging rule formulated by the PCRF to a Policy and Control Enforcement Function (PCEF) for enforcement. At the same time, the PCRF also needs to ensure consistency between these rules and user profile information. The basis for the PCRF to formulate the policy and charging rules includes: service-related information obtained from the AF, policy control and charging related user policy charging control profile information obtained from a Subscription Profile Repository (SPR), and information of a bearer-related network obtained from PCEF through a Gx interface.
The PCEF is generally located in a Gate-Way (GW) to carry out PCRF-developed policy and charging rules on a bearing plane. The PCEF detects the service data traffic in accordance with a service data traffic filter in the rules sent by PCRF, thereby carrying out PCRF-developed policy and charging rules on these service data traffic. When bearer is established, the PCEF performs resource allocation according to the rules sent by the PCRF, and performs the gating control in accordance with the information provided by the AF. At the same time, the PCEF triggers and reports an event occurred on the bearer network according to an event subscribed by the PCRF, In accordance with the charging rules sent by the PCRF, the PCEF carries out a corresponding service data traffic charging operation. The charging may be either online or offline. In the case of the online charging, the PCEF needs to perform credit management together with an Online Charging System (OCS). In the case of the offline charging, related charging information is exchanged between the PCEF and an Offline Charging System (OFCS). Here, the interface between the PCEF and the PCRF is a Gx interface, the interface between the PCEF and the OCS is a Gy interface, and the interface between the PCEF and the OFCS is a Gz interface. The PCEF may also be enhanced to have a Traffic Detection Function (TDF). The PCEF may perform application detection in accordance with locally configured or PCRF-issued ADC rules including Application Detection and Control (ADC) policies, and perform policy enforcement (such as gating control, redirection and bandwidth limitation). The PCEF is generally located on a gateway of the network, such as a Packet Data Network Gateway (PDN-GW) of the EPS, a GPRS Gateway Support Node (GGSN) in General Packet Radio Service (GPRS), and a Packet Data Gateway (PDG) in an Interworking WLAN (I-WLAN).
The TDF may also be deployed independently. In this case, the TDF is connected with the PCRF through an Sd interface, and may perform application detection and policy enforcement according to preconfigured or PCRF-issued ADC rules. The PCRF provides the TDF with the ADC rules, or activates TDF preconfigured rules. Policy control enforcement operations of an independent TDF function include the gating control, the redirection and the bandwidth limitation. The TDF reports related events and information of detected services/traffics to the PCRF, for example, the TDF reports beginning and ending of the detected services/traffics to the PCRF, sends service data traffic descriptions to the PCRF, and transfers signaling of service detection and policy rules coming from the PCRF and being used for traffic detection.
A Bearer Binding and Event Reporting Function entity (BBERF) is generally located in an access network gateway. For example, when a User Equipment accesses an EPS through an E-UTRAN and a Proxy Mobile Internet Protocol version 6 (PMIPv6) is used between a Serving Gateway (S-GW) and a Packet Gateway (P-GW), the BBERF exists in the S-GW. When the User Equipment accesses through a trusted non-3GPP access network, the BBERF also exists in the trusted non-3GPP access gateway.
User policy charging control profile information related to policy control and charging is stored in the Subscription Profile Repository (SPR). The interface between the SPR and the PCRF is an Sp interface.
The OCS and the PCEF work together to accomplish user credit control and management in the online charging mode.
The OFCS and the PCEF work together to accomplish a charging operation in the offline charging mode.
The above PCC architecture, through individual function entities, accomplishes policy charging control over an IP Connectivity Access Network (IP-CAN) session that the UE establishes to access a Packet Data Network (PDN).
In the prior art, the PCEF-enhanced ADC function supports a solicited report mode, and an independent TDF supports both solicited report and unsolicited report modes.
In the solicited report mode, the PCRF will issue ADC rules to the PCEF/TDF of enhanced ADC or activate predefined rules on the PCEF/TDF of enhanced ADC, and inform the PCEF/TDF of enhanced ADC about which services need to be detected and reported to the PCRF.
In the unsolicited report mode, ADC rules are preconfigured and which services needing to be detected and reported is predefined in TDF. It is assumed in the unsolicited report mode that a user agrees that no solicitation is required, and the unsolicited report mode is enforceable without requiring activation of the PCRF.
However, the prior art has not solved the following problems: when the UE roams and is in a visited access scenario, such as the scenario shown in FIG. 2, how a Home Policy and Charging Rule Function (H-PCRF) will distinguish the ADC mode (whether it is the ADC function for the solicited report mode or the unsolicited report mode) of a Visited Public Land Mobile Network (VPLMN), and the H-PCRF cannot make the right decision according to the ADC mode of the VPLMN: whether it is necessary to transfer ADC rules to a Visit Policy and Charging Rule Function (V-PCRF) through the S9 interface; the VPLMN that supports a different ADC mode from a Home Public Land Mobile Network (HPLMN) cannot correctly perform the ADC function on the UE to detect and report application information, that is, when the UE roams to a visited network and is in the visited access scenario, the HPLMN and the VPLMN cannot correctly make decisions and perform the ADC function.
How to enable the H-PCRF to correctly distinguish the ADC mode of the VPLMN, so as to make the right decisions and correctly perform the ADC function has become a problem to be solved by the disclosure.